Novel Genotypes of the Subtropical Grass \u3cem\u3eEragrostis Curvula\u3c/em\u3e for the Analysis of Apomixis (Diplospory)

Eragrostis curvula (Schrad.) Nees is a variable grass native to Southern Africa. Its several forms, known as lovegrasses, were introduced to Australia, USA and Argentina as forage perennial grasses. Apomixis is a common trait in the genus Eragrostis, with diplospory being the most frequent type. Sexual reproduction also occurs in Eragrostis, although not frequently. Since most tetraploid Eragrostis lines are apomictic, the generation of a sexual tetraploid strain is a requirement for linkage analysis of the gene(s) governing the apomictic character. Furthermore, isogenic lines of the same ploidy, reproducing alternatively by sexuality or apomixes, represent an ideal system for comparative transcriptome analysis. The aim of this work was the generation and characterization of two novel genotypes of E. curvula: a dihaploid strain obtained in vitro from an apomictic cultivar and a tetraploid plant derived from the dihaploid after chromosome duplication

Dynamics of chromatin accessibility and gene regulation by MADS-domain transcription factors in flower development.

BACKGROUND: Development of eukaryotic organisms is controlled by transcription factors that trigger specific and global changes in gene expression programs. In plants, MADS-domain transcription factors act as master regulators of developmental switches and organ specification. However, the mechanisms by which these factors dynamically regulate the expression of their target genes at different developmental stages are still poorly understood. RESULTS: We characterized the relationship of chromatin accessibility, gene expression, and DNA binding of two MADS-domain proteins at different stages of Arabidopsis flower development. Dynamic changes in APETALA1 and SEPALLATA3 DNA binding correlated with changes in gene expression, and many of the target genes could be associated with the developmental stage in which they are transcriptionally controlled. We also observe dynamic changes in chromatin accessibility during flower development. Remarkably, DNA binding of APETALA1 and SEPALLATA3 is largely independent of the accessibility status of their binding regions and it can precede increases in DNA accessibility. These results suggest that APETALA1 and SEPALLATA3 may modulate chromatin accessibility, thereby facilitating access of other transcriptional regulators to their target genes. CONCLUSIONS: Our findings indicate that different homeotic factors regulate partly overlapping, yet also distinctive sets of target genes in a partly stage-specific fashion. By combining the information from DNA-binding and gene expression data, we are able to propose models of stage-specific regulatory interactions, thereby addressing dynamics of regulatory networks throughout flower development. Furthermore, MADS-domain TFs may regulate gene expression by alternative strategies, one of which is modulation of chromatin accessibility

SAT0739-HPR Patients' preferences toward characteristics of treatment with biological agents differ according to experience with their rheumatic disease and treatment received or prescribed: results from the cara study

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Patients’, physicians’, nurses’, and pharmacists’ preferences on the characteristics of biologic agents used in the treatment of rheumatic diseases

Objective: To estimate preferences in relevant treatment characteristics evaluated by different groups involved in the management of patients with rheumatic diseases. Subjects and methods: We surveyed patients with rheumatic diseases, and rheumatologists, nurses, and pharmacists with experience in treatment with/provision of biologic drugs for these patients. Through a discrete choice experiment, participants evaluated 16 possible scenarios in which pairs of similarly efficacious treatments were described with six characteristics: 1) frequency of administration; 2) mode and place of administration; 3) manner, helpfulness, efficiency, and courtesy of health personnel; 4) frequency of reactions at the site of drug administration; 5) severity of generalized undesired/allergic reactions; and 6) additional cost. The direction and strength of preferences toward each characteristic level and the relative importance of each characteristic were estimated through a random-effects conditional logistic regression model. Results: In total, 513 patients, 110 rheumatologists, 51 nurses, and 46 pharmacists from 30 centers in Italy participated. Characteristics 3, 4, and 6 were the most important for every subgroup; 1 was least important for patients and rheumatologists, 2 was least important for pharmacists, and 2 and 5 were least important for nurses. For characteristic 2, pharmacists preferred subcutaneous self-injection with a syringe; nurses preferred assisted infusion at an infusion center close to the patient\u2019s home; patients and rheumatologists preferred subcutaneous self-injection with a pen. Conclusion: The different preferences for some characteristics shown by the different groups can play an important role, together with purely clinical aspects, in the choice and consequent benefit of treatments, contributing also to a more satisfactory use of resources

Feto-Placental Atherosclerotic Lesions in Intrauterine Fetal Demise: Role of Parental Cigarette Smoking

The atherogenic effect of cigarette smoking is already recognizable in coronary arteries of fetuses in the last gestational weeks. In this study we analyzed the atherogenic effect of mother’s and father’s smoking habit on coronary arteries and even on adnexa of 30 human fresh fetuses died from 32 to 41 gestational weeks. In 12 cases only the mothers of the victims were cigarette smokers, in 7 cases only the fathers were smokers, whereas in 11 cases nobody smoked

Delayed diagnosis of coeliac disease increases cancer risk

This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

Functional Specialization of the Plant miR396 Regulatory Network through Distinct MicroRNA–Target Interactions

MicroRNAs (miRNAs) are ∼21 nt small RNAs that regulate gene expression in animals and plants. They can be grouped into families comprising different genes encoding similar or identical mature miRNAs. Several miRNA families are deeply conserved in plant lineages and regulate key aspects of plant development, hormone signaling, and stress response. The ancient miRNA miR396 regulates conserved targets belonging to the GROWTH-REGULATING FACTOR (GRF) family of transcription factors, which are known to control cell proliferation in Arabidopsis leaves. In this work, we characterized the regulation of an additional target for miR396, the transcription factor bHLH74, that is necessary for Arabidopsis normal development. bHLH74 homologs with a miR396 target site could only be detected in the sister families Brassicaceae and Cleomaceae. Still, bHLH74 repression by miR396 is required for margin and vein pattern formation of Arabidopsis leaves. MiR396 contributes to the spatio-temporal regulation of GRF and bHLH74 expression during leaf development. Furthermore, a survey of miR396 sequences in different species showed variations in the 5′ portion of the miRNA, a region known to be important for miRNA activity. Analysis of different miR396 variants in Arabidopsis thaliana revealed that they have an enhanced activity toward GRF transcription factors. The interaction between the GRF target site and miR396 has a bulge between positions 7 and 8 of the miRNA. Our data indicate that such bulge modulates the strength of the miR396-mediated repression and that this modulation is essential to shape the precise spatio-temporal pattern of GRF2 expression. The results show that ancient miRNAs can regulate conserved targets with varied efficiency in different species, and we further propose that they could acquire new targets whose control might also be biologically relevant

Finite groups acting on hyperelliptic 3-manifolds

We consider 3-manifolds admitting the action of an involution such that its space of orbits is homeomorphic to S3. Such involutions are called hyperelliptic as the manifolds admitting such an action. We consider finite groups acting on 3-manifolds and containing hyperelliptic involutions whose fixed-point set has r > 2 components. In particular we prove that a simple group containing such an involution is isomorphic to PSL(2,q) for some odd prime power q, or to one of four other small simple groups